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Radiation Protection

What are the risks from radiation exposure from medical imaging?

There are benefits and risks associated with any medical procedure, and you should discuss any concerns you have with your doctor. In general, the benefits of needed medical imaging far outweigh the risks. For imaging procedures that use ionizing radiation, such as CT scans, fluoroscopy and conventional x-ray imaging, medical professionals are trained to keep patient doses as low as reasonably achievable (ALARA). Medical professionals are encouraged to optimize doses, which means using the least amount of radiation required to provide adequate image quality or imaging guidance (for fluoroscopy). This optimization or ALARA process minimizes the patient dose of radiation, while still allowing the medical professional to obtain valuable information for treatment decisions.

There are studies of large populations exposed to radiation that have demonstrated slight increases in cancer risk even at low levels of radiation exposure, particularly in children. To be safe, doctors should presume that even low doses of radiation may cause some slight increase in risk. Optimizing patient doses is particularly important in the case of radiation doses to children. In the case of adults, any individual's cancer risk might be higher or lower depending on a number of factors, including age, lifestyle and heredity.

Return to Frequent Questions about Radiation Protection.